If the Enhanced Applet shell detects the absence of these settings, it will disable the Check For Updates menu item. If you feel you’ve done everything these instructions call be, you can email me a copy of your applet and I’ll check into the problem for you.

I’ve replied to @Tekl privately on this, but the answer bears repeating here. There is a bug in Script Debugger’s enhanced applet shell that prevents the Check For Updates command from being enabled. This will be corrected in the upcoming Script Debugger 7.0.5 maintenance release.